I would call myself such. How do I join a group? Haven't seen how that works yet.

I would call myself a spiritual atheist. For me it means that I believe there is another plane of existence once we die. But it’s not anything to do with a god. I probably wouldn’t be that except that I had an experience within a few hours after my mother’s mother died where she came to me in a dream to tell me it was going to be okay. That probably wouldn’t mean much, except that I wasn’t aware she was dead until that dream. Of course it’s arguable as to whether any of it is real. But it was something very personal for me to which I am still trying to understand today. There may not be any spiritual plane of existence. But until I can explain that dream I won’t rule it out. FYI, I’ve had a couple of other similar things happen with my uncle who I was very close to. So it has only been reinforced since then.

There are many examples of spiritual practices which do not require belief in gods or the supernatural. American Zen Buddhism, for example. Various yogic and meditation practices. That sort of thing.

What is a "spiritual atheist"? I'm in earnest, no sarcasm intended whatsoever.